fix: bug-fix sweep across node, audio, render, plugin subsystems

Node core:
- MathNode/TrigonometryNode combo strings realigned with Operation enums
- mathbase scalar/vector operand pick no longer uses bitwise type checks
- NodeSetPositionAndDependenciesRecursively moves dependencies again
- RemoveAllKeyframes undo actually restores keyframes
- NodeGroup GetInputName null-deref guard, passthrough ids use input id
- NodeValueTable::Has is an exact type match; tag fallback only for
  empty tags; kStrCombo/kPushButton get data type names
- delete_all_keyframes no longer loops forever on unparented keyframes;
  keyframe-load failures propagate; rational interpolation falls back to
  double; OpacityEffect no longer leaks its internal MathNode

Audio/footage:
- AudioVisualWaveform: GetSummaryFromTime underflow OOB read, TrimIn
  prepend length bookkeeping, OverwriteSums source channel indexing
- PanNode inserts the pan value into the sample job (keyframed pan
  works); OutputParamsChanged is emitted on device change; PortAudio
  device indices are validated before Pa_GetDeviceInfo
- Footage: AdjustTimeByLoopMode no longer hangs/UBs on degenerate
  lengths, GetStreamIndex bounds-checked, CheckFootage clears stale
  state on missing files, failed probes are not cached,
  FootageDescription::Load requires its own root element

Render/track:
- ViewerOutput pushes the tagged samples value; TrackList disconnects
  the track-height lambda; GetTrackFromReference validity check
- RenderManager dummy backend: null-initialized threads, guarded
  decoder-cache/timer paths; Renderer::Destroy releases color cache
  shaders/textures; unknown dynamic backends no longer alias to oakgl
- SharedMemoryRegion POSIX attach validates segment size; ReadMessage
  skips blank lines instead of failing; GC counter clamped;
  IsRenderingCustomRange implemented; TimeOffsetNode gets a true
  inverse OutputTimeAdjustment; zero-speed clips return the held frame

Plugin/nodes:
- OliveClip: stored default region of definition is honored, on-demand
  images are cached; OliveHost sets host identity properties and logs
  instead of showing modal dialogs offscreen; Plugin.h dead decls gone
- DespillNode guards graph-less use with Rec.709 fallback; description
  typos fixed (despill, swirl); mosaic applies when only one axis
  matches; Windows-only Project filename separator test fixed

tests/gtest/sequence_test.cpp

@@ -97,6 +97,14 @@ TEST(Sequence, DefaultState)
 				  olive::Track::Reference(olive::Track::kVideo, 0)),
 			  nullptr);
 
+	// Invalid and out-of-range reference types return null instead of crashing
+	EXPECT_EQ(sequence.GetTrackFromReference(
+				  olive::Track::Reference(olive::Track::kNone, 0)),
+			  nullptr);
+	EXPECT_EQ(sequence.GetTrackFromReference(
+				  olive::Track::Reference(olive::Track::kCount, 0)),
+			  nullptr);
+
 	// Length verification over empty track lists keeps everything at zero
 	sequence.VerifyLength();
 	EXPECT_EQ(sequence.GetLength(), olive::core::rational(0));
@@ -282,6 +290,15 @@ TEST(Sequence, TrackDisconnectResetsTrackState)
 						 ++sequence_removed;
 					 });
 
+	// While connected, track height changes are forwarded by the list
+	int height_changed = 0;
+	QObject::connect(list, &olive::TrackList::TrackHeightChanged,
+					 [&height_changed](olive::Track *, int) {
+						 ++height_changed;
+					 });
+	first->SetTrackHeight(first->GetTrackHeight() + 1.0);
+	EXPECT_EQ(height_changed, 1);
+
 	olive::Node::DisconnectEdge(first, list->track_input(0));
 
 	EXPECT_EQ(list_removed, 1);
@@ -311,6 +328,10 @@ TEST(Sequence, TrackDisconnectResetsTrackState)
 	EXPECT_EQ(sequence->GetTrackFromReference(
 				  olive::Track::Reference(olive::Track::kVideo, 1)),
 			  nullptr);
+
+	// Height changes on the removed track must no longer be forwarded
+	first->SetTrackHeight(first->GetTrackHeight() + 1.0);
+	EXPECT_EQ(height_changed, 1);
 }
 
 TEST(TrackList, CacheOrderFollowsArrayIndex)